The burn-in problem can be divided in a short-term burn-in and a long-term burn-in. On a plasma display panel (PDP), two kinds of ghost images are existing:                in “short term burn-in”: the ghost image (3 to 5% of its original brightness) is mainly a positive image (i.e. “burned” cells are brighter than others) which disappear after a short time (some minutes up to some hours). The origin is not completely clear yet but it seems that this effect is related to some kind of charges which have been accumulated during the time a cell stays ON. Later these charges increase the luminance emitted by the cell even if a priming is done in the frame period.        in “long term burn-in”: the stable sticking image is a negative image (i.e. “burned” cells are darker than others) related to a kind of aging of the plasma cell. The cumulative amplitude can go up to 50% loss of luminance. The long term burn-in is the more critical issue since this effect is not reversible and could reach 50% luminance loss. At the beginning of the PDP lifetime, the aging process is quite strong and leads quickly to create disturbing ghost images, above all for professional applications using static pictures. Later this process decreases.In the case of cathode ray tube (CRT) technology, especially for personal computer (PC) monitors, this effect is really an issue, that is why they dispose today of a screen saver in order to prevent a strong marking of the screen. One approach to long-term burn-in protection is to invert the static pictures in order to burn the entire PDP panel in the same way. This requires to know the picture content and this method is strongly limited by power consumption of the panel. Another approach is to use a kind of jittering in picture position on professional PDPS. Thereby the picture is regularly translated a bit in all directions. Nowadays, the flat display panels are often protected from burn-in effect by shifting the picture in a certain manner (hereinafter defined as a pattern) as defined by the manufacturer. A known solution to reduce burn-in effect is to shift pictures constantly (e.g. 4 pixels left, 4 pixels up, 4 pixels right, 4 pixels down, and so on). One disadvantage is that this shifting of the picture is visible to the user and thus may be annoying.        